Characteristics of masonry units from iron ore tailings

This paper deals with an experimental study on masonry units made of iron ore tailings in compressed earth block. Compressed earth blocks (CEB) or stabilised mud blocks (SMB) are widely accepted as energy efficient alternatives to burnt clay bricks. Natural river sand is often used to obtain optimum soil gradation in the production of SMB. In order to reduce adverse impacts of indiscriminate mining of natural sand, iron ore tailings (IOT), which is a mine waste, is used as an alternate to the natural river sand. Based on the gradation of soil used for production of SMB, optimum mix proportion of soil, sand and cement was fixed and the sand fraction was replaced by IOT at 25%, 50% and 100%. The block characteristics like wet compressive strength, water absorption, initial rate of absorption and linear elongation were examined and discussed. From the experimental results it is found that considerable amount of sand can be replaced by IOTwithout compromising desirable characteristics of SMB used for masonr

Garnet mineral chemistry as a provenance indicator for the modern beach sediments of north-eastern Andhra Pradesh, east coast of India

917-924The provenance of garnets from coastal sediments between the Nagavali and Vamsadhara river mouths, east coast of India were studied using garnet molecular proportions. This mineral chemical electron micro probe analytical data have been correlated with published garnet chemistry from various litho units of the eastern ghats granulite belt to understand provenance. The present study reveals that the garnets with molecular proportions of almandine (Alm. 50-56%), pyrope (Py. 33-43%) and traces of grossular (Gr. 5%) were derived from charnockite suite of rocks. The major portion (83%) of the studied garnets is derived from khondalite (metapelitic) suite of rocks susceptible for physical weathering due to large areal exposure and minor proportion (17%) is derived from charnockite suite of rocks which due to less coverage in drainage basis is not susceptible for mechanical weathering

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Not AvailableFCV tobacco is grown under irrigated conditions in Northern light soils (NLS) of Andhra Pradesh. These soils are sandy to sandy loam in texture with high hydraulic conductivity and low water retentivity, acidic in reaction, very low in organic carbon, medium to high in available phosphorus and low to medium in available potassium. Available boron in these soils is in the range of 0.16 to 0.48 ppm. Boron is one of the important micronutrients essential for normal and healthy growth of tobacco, because of its participation in protein metabolism, alkaloid production, translocation, interaction with elements such as calcium and potassium, and its consequent effect on the yield and quality of tobacco crop (Tso, 1990). Earlier studies by Murthy et al. (1985) revealed that B – content in FCV tobacco grown in Northern light soils of Andhra Pradesh was in the range of sufficiency. However, since the crop is being cultivated continuously over years and also the new high yielding variety Kanchan was introduced, whose requirement of nutrients is very high and also since B – carrying inorganic fertilizers are not being used in raising the crop and as the soils are sandy to sandy loam in nature, there may be chances for B – depletion. In view of all these factors, studies on monitoring of boron were taken up for several years by collecting leaf samples from various locations from farmers’ fields covering entire northern light soil area, the results of which are presented in this paper.Not Availabl

From QTL to variety- Harnessing the benefits of QTLs for drought, flood and salt tolerance in mega rice varieties of India through a multi-institutional network.

Rice is a staple cereal of India cultivated in about 43.5 Mha area but with relatively low average productivity. Abiotic factors like drought, flood and salinity affect rice production adversely in more than 50% of this area. Breeding rice varieties with inbuilt tolerance to these stresses offers an economically viable and sustainable option to improve rice productivity. Availability of high quality reference genome sequence of rice, knowledge of exact position of genes/QTLs governing tolerance to abiotic stresses andavailability of DNA markers linked to these traits has opened up opportunities for breeders to transfer the favorable alleles into widely grown rice varieties through marker-assisted back cross breeding (MABB). Alarge multi-institutional project, “From QTL to variety: marker-assisted breeding of abiotic stress tolerant rice varieties with major QTLs for drought, submergence and salt tolerance” was initiated in 2010 with funding support from Department of Biotechnology, Government of India, in collaboration with Interna-tional Rice Research Institute, Philippines. The main focus of this project is to improve rice productivity inthe fragile ecosystems of eastern, northeastern and southern part of the country, which bear the brunt ofone or the other abiotic stresses frequently. Seven consistent QTLs for grain yield under drought, namely,qDTY1.1, qDTY2.1, qDTY2.2, qDTY3.1, qDTY3.2, qDTY9.1and qDTY12.1are being transferred into submergence IR64-Sub1. To address the problem of complete submergence due to flash floods in the major river basins,the Sub1 gene is being transferred into ten highly popular locally adapted rice varieties namely, ADT 39,ADT 46, Bahadur, HUR 105, MTU 1075, Pooja, Pratikshya, Rajendra Mahsuri, Ranjit, and Sarjoo 52. Further,to address the problem of soil salinity, Saltol, a major QTL for salt tolerance is being transferred into sevenpopular locally adapted rice varieties, namely, ADT 45, CR 1009, Gayatri, MTU 1010, PR 114, Pusa 44 andSarjoo 52. Genotypic background selection is being done after BC2F2stage using an in-house designed50K SNP chip on a set of twenty lines for each combination, identified with phenotypic similarity in the field to the recipient parent. Near-isogenic lines with more than 90% similarity to the recipient parentare now in advanced generation field trials. These climate smart varieties are expected to improve rice productivity in the adverse ecologies and contribute to the farmer’s livelihood